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1.
Anat Rec (Hoboken) ; 306(10): 2610-2620, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36883757

RESUMEN

Natural history data are important for a better understanding of distinct aspects of snake biology, and this information in scarce on Scolecophidia. Here we focus on sexual maturity and sexual dimorphism within a population of Amerotyphlops brongersmianus from the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. The smallest sexually active male and female showed snout-vent length of 117.5 and 158.4 mm, respectively. Females had statistically significant larger body and head length sizes, whereas males had longer tails. Juveniles showed no sexual dimorphism for any analyzed feature. Secondary vitellogenic follicles had a more opaque, yellowish/darker aspect, being larger than 3.5 mm. We reinforce that in addition to traditional features for determining sexual maturity, morphological and histological characteristics of kidneys should be evaluated in males, as well as the morphology of the infundibulum in females. Histological data show development of seminiferous tubules and presence of spermatozoa in males, and infundibulum receptacles and uterine glands in females as a sign of sexual maturity. This type of information is essential for a more accurate description of data on sexual maturity, allowing access to information on the development of reproductive structures that are not available macroscopically.


Asunto(s)
Caracteres Sexuales , Serpientes , Animales , Femenino , Masculino , Brasil , Reproducción
2.
Anat Rec, v. 306, n. 10, p. 2610-2620, mar. 2023
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-4826

RESUMEN

Natural history data are important for a better understanding of distinct aspects of snake biology, and this information in scarce on Scolecophidia. Here we focus on sexual maturity and sexual dimorphism within a population of Amerotyphlops brongersmianus from the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. The smallest sexually active male and female showed snout-vent length of 117.5 and 158.4 mm, respectively. Females had statistically significant larger body and head length sizes, whereas males had longer tails. Juveniles showed no sexual dimorphism for any analyzed feature. Secondary vitellogenic follicles had a more opaque, yellowish/darker aspect, being larger than 3.5 mm. We reinforce that in addition to traditional features for determining sexual maturity, morphological and histological characteristics of kidneys should be evaluated in males, as well as the morphology of the infundibulum in females. Histological data show development of seminiferous tubules and presence of spermatozoa in males, and infundibulum receptacles and uterine glands in females as a sign of sexual maturity. This type of information is essential for a more accurate description of data on sexual maturity, allowing access to information on the development of reproductive structures that are not available macroscopically.

3.
Anat Rec ; : 1–12, 2020.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17403

RESUMEN

Amerotyphlops brongersmianus (Vanzolini, 1976) is distributed in Brazil from the Atlantic Rainforest to the Cerrado biome. Only few studies have focused on the gross anatomy, reproductive organs, and histological data of typhlopids. We accessed information from the anatomy of gonads of 95 individuals collected at different months in the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. This included histological sections of the testes, ductus deferens and sexual segment of kidney in males, and oviducts in females, from which fecundity was determined. Results revealed a correlation between gross morphology and histology of the reproductive system. Testes volume increased during spermatogenesis, and the ductus deferens diameter increased with the presence of spermatozoa. Additionally, changes occurred in kidney morphology, which showed a smooth or rough surface, the latter corresponding to the development of the sexual segment of the kidney (SSK). Spermatozoa were found inside the lumen of the SSK of some males. Females lacked left oviducts and showed changes in morphological and histological aspects of the right oviducts throughout the year. In summer and spring the uterus showed undeveloped structures, while during winter this organ showed conspicuously developed glands and appeared pleated and opaque upon gross examination. The infundibulum was pleated in most females throughout the year and one female had spermatozoon in a receptacle located in the posterior infundibulum. In spring this organ was enlarged compared to winter, with a thinner epithelium. Fecundity corresponded to 7–11 eggs.

4.
Anat Rec, p. 1-12, jan. 2020
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2922

RESUMEN

Amerotyphlops brongersmianus (Vanzolini, 1976) is distributed in Brazil from the Atlantic Rainforest to the Cerrado biome. Only few studies have focused on the gross anatomy, reproductive organs, and histological data of typhlopids. We accessed information from the anatomy of gonads of 95 individuals collected at different months in the Restinga de Jurubatiba National Park, Rio de Janeiro state, Brazil. This included histological sections of the testes, ductus deferens and sexual segment of kidney in males, and oviducts in females, from which fecundity was determined. Results revealed a correlation between gross morphology and histology of the reproductive system. Testes volume increased during spermatogenesis, and the ductus deferens diameter increased with the presence of spermatozoa. Additionally, changes occurred in kidney morphology, which showed a smooth or rough surface, the latter corresponding to the development of the sexual segment of the kidney (SSK). Spermatozoa were found inside the lumen of the SSK of some males. Females lacked left oviducts and showed changes in morphological and histological aspects of the right oviducts throughout the year. In summer and spring the uterus showed undeveloped structures, while during winter this organ showed conspicuously developed glands and appeared pleated and opaque upon gross examination. The infundibulum was pleated in most females throughout the year and one female had spermatozoon in a receptacle located in the posterior infundibulum. In spring this organ was enlarged compared to winter, with a thinner epithelium. Fecundity corresponded to 7–11 eggs.

5.
Biota Neotrop. (Online, Ed. ingl.) ; 19(2): e20190727, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-989412

RESUMEN

Abstract: We provide an inventory checklist of the amphibians from Parque Nacional da Restinga de Jurubatiba (PNRJ), a sandy coastal environment in southeastern Brazil. As a result of three years of surveys, from August 2013 to June 2016, a total of 36 amphibians species were recorded - one Gymnophiona (Typhlonectidae) and 35 species of five anuran families: Bufonidae (2 species), Craugastoridae (1), Hylidae (21), Leptodactylidae (8), and Microhylidae (3). One specie is reported for the first time for the restinga ecosystem (Chthonerpeton braestrupi) and 24 species were recorded for the first time to the PNRJ. This result reinforces the importance of long-term studies for accurate knowledge of the biodiversity. Considering that the biodiversity of the fragments of the sandy coastal environments in the state of Rio de Janeiro is poorly known, the present study provided a more detailed knowledge about different aspects of the biodiversity in the PNRJ, contributing to the preservation of this threatened ecosystem.


Resumo: Nós fornecemos um inventário dos anfíbios do Parque Nacional da Restinga de Jurubatiba (PNRJ), uma zona costeira de ambiente arenoso no sudeste do Brasil. Como resultado de três anos de pesquisas, no período de Agosto de 2013 a Junho de 2016, foram registradas um total de 36 espécies de anfíbios - uma Gymnophiona (Typhlonectidae) e 35 espécies de cinco famílias de anuros: Bufonidae (2 espécies), Craugastoridae (1), Hylidae (21), Leptodactylidae (8) e Microhylidae (3). Uma espécie é registrada pela primeira vez para o ecossistema de restinga (Chthonerpeton braestrupi) e 24 espécies foram registradas pela primeira vez para o PNRJ. Este resultado reforça a importância de estudos de longo prazo para um conhecimento preciso da biodiversidade. Considerando que a biodiversidade dos fragmentos dos ambientes costeiros no estado do Rio de Janeiro é pouco conhecida, o presente estudo proporcionou um conhecimento mais detalhado sobre os diferentes aspectos da biodiversidade no PNRJ, contribuindo para a preservação desse ecossistema ameaçado.

6.
Zootaxa ; 4137(1): 121-8, 2016 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-27395746

RESUMEN

Recently a new species of bombyliid fly, Marleyimyia xylocopae, was described by Marshall & Evenhuis (2015) based on two photographs taken during fieldwork in the Republic of South Africa. This species has no preserved holotype. The paper generated some buzz, especially among dipterists, because in most cases photographs taken in the field provide insufficient information for properly diagnosing and documenting species of Diptera.


Asunto(s)
Dípteros/clasificación , Entomología/normas , Animales , Clasificación/métodos , Dípteros/anatomía & histología , Femenino , Masculino , Sudáfrica
7.
Zootaxa ; 4007(1): 63-81, 2016 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-26623921

RESUMEN

Hydrodynastes bicinctus was described with no type material or locality and it has two subspecies currently recognized that are not taxonomically well defined. We tested the validity of the two subspecies through meristic, morphometric, and color pattern characters. Two apparently distinct color patterns of H. bicinctus were noticed, one from the Cerrado open formations and the other from the Amazon rainforest. These aforementioned patterns, however, exhibited a high degree of geographic overlap and many specimens showed a blended pattern. Based on these results we propose synonymizing H. bicinctus schultzi with the nominal taxon. Furthermore, we designate a neotype for the species, present data on geographic distribution, and provide morphological descriptions of the hemipenis, cephalic glands, and skull.


Asunto(s)
Colubridae/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Colubridae/anatomía & histología , Colubridae/crecimiento & desarrollo , Femenino , Masculino , Tamaño de los Órganos
8.
Zootaxa ; 3881(6): 563-75, 2014 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-25543653

RESUMEN

We describe a new species of Chironius Fitzinger, 1826 from the highlands of Chapada Diamantina, state of Bahia, Brazil. The new species is distinguished from all currently recognized congeners by a unique combination of states of characters on coloration, scale counts, scale ornamentation, and hemipenis. The new species closely resembles Chironius flavolineatus (Jan, 1863) in color pattern, but differs from the later taxon by the presence of two to four posterior temporal scales; cloacal shield entire; six to ten rows of keeled dorsal scales at midbody; ventral scales with posterior dark edges forming conspicuous transverse bars along almost the entire venter; conspicuous dark longitudinal stripes (in "zigzag") in the midventral portion of subcaudals; region of medial constriction of hemipenis slightly covered with spinules separating calyces of apex from spines below region of constriction; and sulcus spermaticus situated on convex face of hemipenis in lateral view. The new species is apparently restricted to Chapada Diamantina, corroborating the biological importance of this region from a conservational perspective.


Asunto(s)
Colubridae/anatomía & histología , Colubridae/clasificación , Animales , Brasil , Femenino , Masculino
9.
Zootaxa ; 3794: 134-42, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24870316

RESUMEN

The snake genus Chironius Fitzinger, 1826 is endemic to the Neotropical region, occurring from Honduras to Uruguay and northeastern Argentina. Some species of the genus have taxonomic and/or nomenclatural problems, such as C. flavolineatus which lacks agreement in the literature about its authorship and type locality. Some researchers have been suggesting Jan (1863) as the author of the species since he first described C. flavolineatus based on two specimens. However, other researchers report that Jan's description is so incomplete that it is not possible to ascertain what snake he had in mind and therefore suggest Boettger (1885) as the author, since he was the first to provide a detailed description of the species. In the present study one of the syntypes of C. flavolineatus, supposedly destroyed in Second World War, was found. Thus, the taxonomic identity of C. flavolineatus was redefined, its lectotype was designated and the authorship of the taxa is attributed to Jan (1863).


Asunto(s)
Colubridae/clasificación , Animales , Colubridae/anatomía & histología , Masculino , Terminología como Asunto
10.
PLoS One ; 8(3): e59736, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23527261

RESUMEN

Based on comprehensive distributional records of the 23 species currently assigned to the lizard genus Tropidurus, we investigated patterns of endemism and area relationships in South America. Two biogeographic methods were applied, Parsimony Analysis of Endemicity (PAE) and Brooks Parsimony Analysis (BPA). Two areas of endemism were detected by PAE: the first within the domains of the semiarid Brazilian Caatinga, which includes seven endemic species, and the second in the region of the Serranía de Huanchaca, eastern Bolivia, in which three endemic species are present. The area cladograms recovered a close relationship between the Atlantic Forest and areas of the South American open corridor. The results revealed a close relationship among the provinces Caatinga (Cerrado, Parana Forest (Pantanal+Chaco)). The uplift of the Brazilian Central Plateau in the Late Pliocene-Early Pleistocene (4-2 Myr BP) has been interpreted as a major event responsible for isolation and differentiation of biotas along these areas. However, we emphasize that without the establishment of a temporal framework concerning the diversification history of Tropidurus it is premature to correlate cladogenetic events with specific time periods or putative vicariant scenarios. The limiting factors hampering the understanding of the biogeographic history of this genus include (1) the absence of temporal references in relation to the diversification of distinct clades within Tropidurus; (2) the lack of an appropriate taxonomic resolution of the species complexes currently represented by widely distributed forms; and (3) the need for a comprehensive phylogenetic hypothesis. We suggest that these three important aspects should be prioritized in future investigations.


Asunto(s)
Distribución Animal/fisiología , Ecosistema , Lagartos/fisiología , Filogenia , Animales , Sistemas de Información Geográfica , Fenómenos Geológicos , Lagartos/genética , Filogeografía , América del Sur , Especificidad de la Especie
11.
Toxicon ; 55(4): 881-7, 2010 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20036275

RESUMEN

Snakebites are still a critical public health problem in developing countries or isolated areas. In Brazil, the North Region has a high distribution coefficient worsened by the significant number of eventually unreported cases, due to difficulties in access to health services, to the natural geographic barriers and the vast territory. In the Rio Negro area, the species Bothrops atrox, Bothrops brazili, Lachesis muta muta and Bothriopsis taeniata are thought to be the major species responsible for snakebites. The aim of this study was to qualitatively and quantitatively determine the antigenic cross-reactivity and expression of toxins and the immunogenicity of Bothrops venom species of the Amazon and to evaluate the general efficacy of the therapeutic sera. The in vivo assays demonstrated that the defibrinating activity of B. taeniata venom was absent but that the lethal and hemorrhagic properties were more intense than in the B. atrox venom. The results evidence venom variability among the two B. atrox populations from two distinct Amazonian regions, which may reveal a subjacent speciation process. The results point to new aspects that may guide the improvement of anti-Bothropic therapeutic serum.


Asunto(s)
Bothrops/clasificación , Reacciones Cruzadas , Venenos de Crotálidos/inmunología , Animales , Anticuerpos Neutralizantes/inmunología , Western Blotting , Electroforesis en Gel de Poliacrilamida , Femenino , Dosificación Letal Mediana , Masculino , Ratones , Ratas , Ratas Wistar , América del Sur
12.
Toxicon ; 55(4): 881-887, Dec 29, 2009.
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1068248

RESUMEN

Snakebites are still a critical public health problem in developing countries or isolated areas. In Brazil, the North Region has a high distribution coefficient worsened by the significant number of eventually unreported cases, due to difficulties in access to healthservices, to the natural geographic barriers and the vast territory. In the Rio Negro area, the species Bothrops atrox, Bothrops brazili, Lachesis muta muta and Bothriopsis taeniata arethought to be the major species responsible for snakebites. The aim of this study was to qualitatively and quantitatively determine the antigenic cross-reactivity and expression oftoxins and the immunogenicity of Bothrops venom species of the Amazon and to evaluate the general efficacy of the therapeutic sera. The in vivo assays demonstrated that the defibrinating activity of B. taeniata venom was absent but that the lethal and hemorrhagic properties were more intense than in the B. atrox venom. The results evidence venom variability among the two B. atrox populations from two distinct Amazonian regions, which may reveal a subjacent speciation process. The results point to new aspects that mayguide the improvement of anti-Bothropic therapeutic serum.


Asunto(s)
Bothrops/clasificación , Bothrops/inmunología , Toxicidad/análisis , Venenos/análisis , Venenos/inmunología , Venenos/aislamiento & purificación , Ecosistema Amazónico , Viperidae/clasificación
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